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Market Report: Power Tools Breaking the mould Modern rotary and demolition hammers remain popular for hire fleets due to their power, productivity and low vibration. EHN’s Power Tools Specialist, Phil Mist, reviews some of the latest models. Despite lower power tool prices and the subsequent increase in ownership rather than hire, the medium to large rotary and demolition hammer segment remains as important as ever for hire companies, with the most popular weight category being 5-6kg. However, the weights quoted by manufacturers for some products can be confusing. What are described as 5kg hammer drills may vary from just 4.6kg to nearly 7kg. Why companies have not agreed a standard weighing method is baffling. Some weigh tools without a cable, others quote cordless tools without the battery, while the worst offenders are many of the (so-called) 2kg hammer drills, some of which weigh over 3kg. The weight of a machine can influence its operation and the amount of effort required from the operator. All hammer drills rely on their weight to improve their performance, and if you reduce it too much, then the user may have to push harder, with the result that the level of vibration produced may increase. Hammers weighing less than 5kg generally have an SDS Plus tool holder. Heavier ones usually have an SDS Max front end, because of their much larger impact rating, and they typically offer three functions: rotary only mode, rotary hammer action, and, by using a rotation stop system, a breaker mode. The latest 5kg-plus models totally outperform their predecessors. Many have complicated low-vibration systems, soft start to protect the operator, and a low or half impact feature for working close to the edge of concrete. Some have a service light indicating when maintenance is required, and many of the latest models incorporate a multi-position tool holder to enable a demolition hammer to be used at virtually any angle. Optimum shape The optimum shape of medium sized hammer drills or demolition hammers comes down to personal choice. Some operators prefer ‘T’ shaped machines, others always ask for in-line tools. Generally, the larger the machine, the more the designer will veer towards the latter configuration, although some operators feel they are too far away from the action. Makita’s HR3210C AVT, unlike most other medium weight hammers, has an SDS Plus tool holder. It weighs 4.9kg and yet is a three-function machine. It has the manufacturer’s AVT low-vibration system, and the quoted HAV value is only 7.5m/s2 in hammer mode. This figure rises, as with many other such tools, to 10m/s2 in drilling mode, but then the HR3210C, which is powered by an 850watt motor and has a single impact value of 6.4J, is a high-performance tool. Makita also recently introduced a new 8kg hammer (it actually weighs 8.4kg) with an SDS Max tool holder. The HR4511C provides a massive 13J of single impact energy, and has a 1,350watt motor. In hammer mode, it benefits from the AVT system and has an HAV figure of only 7m/s2, which is claimed by Makita to be 50% less than many existing rotary hammer drills. Maximum drilling capacity is rated at 45mm and the maximum hammer core capacity is claimed to be 125mm in diameter. Hitachi has launched the DH40MRY. Described as a 6kg low-vibration rotary hammer (actual weight 6.8kg), it has a 950watt motor and provides a single blow energy rating of 10.5J. It has auto-stop carbon brushes, which help to ensure regular servicing. Hitachi has also introduced a 10kg machine, the DH50MRY. Actually weighing 10.5kg, it has a massive 1,400watt motor and gives an impressive single energy blow rating of 20J. Drilling capacity is 50mm when using a solid drill bit. Finally, Hitachi has unveiled a 6kg (actually 5.9kg) demolition hammer, designated the H45MRY, which has an SDS Max tool holder and in operation provides a single blow rating of an even more impressive 12.7J. More Kango models The name Kango in the hire industry is often used as a generic name for hammer drills and demolition hammers, particularly in the medium to large categories. During the last year, Milwaukee, the current owner of the brand, has launched two new Kango products, namely the 500S breaker and the 545S combi hammer, which appear to be establishing a decent reputation. There now comes news of a forthcoming 8kg rotary hammer. Whilst not yet available to test, the Kango 750S would appear to be a serious contender for hire. The machine is said to weigh 8.3kg and is powered by a massive 1,550watt motor. Milwaukee quotes a single blow energy rating of 16J and says the machine can drill up to a maximum diameter of 50mm with a solid drill bit and up to 150mm diameter using a hammer core. The 750S has a claimed tri-axial vibration level of only 9.5m/s2. Some specifications may change, of course, before the product’s formal launch. Kango/Milwaukee also suggests there might be more new hammer drills later this year and in 2009, so this famous brand, which once seemed likely to disappear in the UK, seems to be making a strong comeback. DeWalt earlier this year up-rated its 10kg hammer, and the result is the D25901K, which has a 1,500watt motor. It has a single blow energy rating of 25J, which can be varied from 5J upwards. Even though this machine has a huge breaking capacity, it has a quoted vibration level of less than 8m/s2, which is extremely low for such a powerful tool. It is one of the few in-line machines launched so far in 2008, and has a cushioned front loop handle, an internal counter balance system to reduce vibration, and a floating rear handle. These features are said to help reduce HAV by more than 50%. Certainly, in tests for EHN, the anti-vibration system seemed to work well. Hilti in the last eight months has introduced two significant products in this category, namely the TE500-AVR demolition hammer and the TE 80 rotary demolition hammer. The former weighs 5.7kg and has a 1,100watt motor. It features the manufacturer’s Active Vibration Reduction (AVR) system, giving a claimed vibration level of only 10.1m/s2, yet it has a single energy blow rating of 7.5J, increasing performance by 40% over previous models. The TE 80 is a 10.2kg rotary hammer drill with a 1,700watt motor. It has a single energy blow rating of 11J, an increase of 30% over its predecessor, and is 40% quicker when drilling, yet it has a vibration level of only 8.8m/s2 due to the AVR system. In addition, it incorporates Active Torque Control (ATC) for operator safety, and a de-coupled rear handle for comfort. Some of the above tools have already been in hire fleets for a few months and are reported to be performing well, which must please the manufacturers, who regard the rigours of hire to be the most demanding environment for equipment. Users enjoy the greater productivity and performance, and with more products expected to be launched later this year, there should certainly be a considerable amount to keep hirers and their customers interested. • Executive Hire News › Archives › July 2008 › Market Report › Breaking the mould
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